There is a service available whereby service information, such as character information, is multiplexed on an FM broadcast radio wave and is transmitted, and thereby the transmitted service information is received by a reception terminal to be displayed on a display means provided on the reception terminal. This service is called "FM teletext broadcasting" and has already been put to a practical use as visual information radio.
According to this FM teletext broadcasting, when an FM broadcast radio wave, which is acquired by frequency-multiplexing display information such as characters and/or numerals on an ordinary broadcast radio wave, is transmitted from an FM broadcasting station on the transmission side, a reception terminal, such as an FM radio receiver, which is equipped with a display like a liquid crystal display receives this FM broadcast radio wave. The reception terminal separates the received information into audio information and display information, and converts this display information to character codes to be displayed on the display to allow a user to see this display information. While listening to an FM radio program, therefore, the user can see information associated with the FM radio program, such as the title of a broadcast music piece, the name of the artist, comments and/or the number of requests. The user can also see news, weather information, traffic information or the like, which is not directly associated with broadcasting, as character information.
There is a plan for a bidirectional service which allows users not only to simply see character information transmitted from an FM broadcasting station but also to send a response to a broadcast quiz or questionnaires or a request or the like to a broadcast program (hereinafter, such response, request or the like will be referred to as return message data).
In this bidirectional service, for example, a user sends return message data via a telephone line to a broadcasting station from a reception terminal equipped with an auto-dialing function.
The broadcasting station that receives the return message data should check for which program each return message data has been sent, and must manage those return message data by performing tedious processing operations, such as collection and editing of the return message data. That is, the FM broadcasting station which receives the return message data must do a large amount of processing.
To reduce the amount processing carried out by the broadcasting station, each user may input through the reception terminal the name and the broadcasting date of a program to which his/her return message data is associated at the time of sending the return message data, or may prepare return message data according to a predetermined form. But, such a burden on users is troublesome.